Help - Vibration When Braking?

[wbwii]

Okay, here is my story. I have a 92 ES300 with over 160K miles, that has developed a vibration when braking. In a nutshell I have replaced:

All 4 shocks (passenger rear was shot, we will get back to the passenger rear problem area)

Replaced all rotors & pads about a year ago

Replaced all calipers two weeks ago, no visual problems with rotors or pads. New brake fluid.

Had the car a lined, the dealership noticed that the passenger rear tire was "chunky". After investigation it looked like someone had sandpapered the tread about ever other 5 inches. Very bizarre and I still do not know why. Replaced two tires, old tires only about two years old.

Checked the codes to see if the ABS system is working properly via abs light on dash, everything checked out okay.

Could the LSPV be the problem? It seems as though the vibrations start in the back but difficult to tell as the whole car shakes initially and if I apply more pressure the vibration lessens.

I need your help, I don't want to take it to the dealership which is 45 minutes away. I don't know if any mechanic in my small town of 6000 people has ever seen this before.

Thanks for your help!

Bill

[bartkat]

I don't know the vibration problem but I expect the flat spotted or cupped tire was at the same corner as the totally bad shock?

[George_Jetson]

The cupped tires are a classic symptom of bad shocks. As far as the vibration, when you replaced the rotors, did you check for runout? Are you positive that the mounting surfaces for the rotors were clean and rust free? If there was and debris on the hub, the rotors will not sit flat on the surface. The best thing to do is check runout. The nest step would be check the rest of the front end for wear.

[TRAILSEEKER]

Okay, here is my story. I have a 92 ES300 with over 160K miles, that has developed a vibration when braking. In a nutshell I have replaced:

All 4 shocks (passenger rear was shot, we will get back to the passenger rear problem area)

Replaced all rotors & pads about a year ago

Replaced all calipers two weeks ago, no visual problems with rotors or pads. New brake fluid.

Had the car a lined, the dealership noticed that the passenger rear tire was "chunky". After investigation it looked like someone had sandpapered the tread about ever other 5 inches. Very bizarre and I still do not know why. Replaced two tires, old tires only about two years old.

Checked the codes to see if the ABS system is working properly via abs light on dash, everything checked out okay.

Could the LSPV be the problem? It seems as though the vibrations start in the back but difficult to tell as the whole car shakes initially and if I apply more pressure the vibration lessens.

I need your help, I don't want to take it to the dealership which is 45 minutes away. I don't know if any mechanic in my small town of 6000 people has ever seen this before.

Thanks for your help!

Bill

[TRAILSEEKER]

The cupped tires are a classic symptom of bad shocks. As far as the vibration, when you replaced the rotors, did you check for runout? Are you positive that the mounting surfaces for the rotors were clean and rust free? If there was and debris on the hub, the rotors will not sit flat on the surface. The best thing to do is check runout. The nest step would be check the rest of the front end for wear.

had same problem it was a warped rotor

[wbwii]

Thanks for the quick replies. I will start with the front rotors and have them turned. Each time I replace rotors I wipe the oil off so there are no slick spots. I will keep everyone informed what happens. I hope rotors that are only a year old are not warped, but this would be the easiest fix.

[eatingupblacktop]

Are these oem rotors?

[branshew]

As was mentioned - warped rotor is the most likely cause. Typically you will feel the vibration transfer through the steering wheel if it is one of the front rotors.

[wbwii]

They are aftermarket rotors, I forget the manufacturer. I went cheap considering how many miles are on the car.

[eatingupblacktop]

They are aftermarket rotors, I forget the manufacturer. I went cheap considering how many miles are on the car.

Then you prob got the crap they make in China! Besides 160 K aint a lot of miles. Sorry to tell you, "Ya get wat Ya pay for"! Don't bother machining them. With the crap metal they're made from, you'll just be making them thinner and more prone to warping. Invest in some decent quality and save yourself the headaches.